1. Field
The present invention relates to a display panel, and more particularly, to an organic electro-luminescence display and a manufacturing method thereof.
2. Background
In recent years, a variety of a magnetic type luminescence display has been developed, and a basic structure of the magnetic type luminescence display is a horizontal array of light emitting devices driving one pixel as an element. As an example of the magnetic type luminescence display, there are a VFE (Vacuum Fluorescence Display), an EL (Electro-luminescence), an LED (Light Emitting Diode), and a FED (Field Emission Display) as well as a PDP (Plasma Display Panel) having a cell as a luminescence device, the cell divided by a discharge area.
Among the magnetic type luminescence displays, particularly, an organic EL display panel enabling to obtain a surface luminescence with high brightness at a low voltage and RGB luminescence with a high degree of purity has come to be the center of attention for a ultra slim size, a light weight, and full color.
The organic EL display forms an organic layer including an emitting layer between a couple of electrodes including an anode applied to a positive voltage and a cathode applied to a negative voltage. In the organic display, by applying voltage between electrodes, an electron from cathode and a hole from anode are injected into each organic layer, and the electrode and the hole are coupled in the organic layer thereby light is emitted. The EL display panel including the organic EL device is described in reference to appended drawings.
FIG. 1 illustrates a floor plan of a conventional organic display panel. As illustrated in the drawing, the organic display panel includes a glass substrate 101, an ITO strip 102 formed in a strip form and arrayed in a line on the glass substrate, a supplement electrode 103 formed in a smaller width than the ITO strip on the ITO strip 102, an organic EL layer 104 having a hole transport layer, the emitting layer, and an electron transport layer piled on the ITO strip 102, an insulating film 106 formed between the ITO strip 102 and a bulkhead, an anode strip 105 crossing the ITO strip 102 on the organic EL layer 104 and formed in a band, a bulkhead 107 formed in the band form between the anode strips 105 for separating the neighboring anode strips 105, and a seal-cover 109 coupled to a substrate having the anode strip 105 by using a sealant 108.
In this case, the organic EL display panel is formed in a structure wherein the organic EL layer 104 is inserted between the ITO strip 102 having one higher work function and the anode strip 105 having one lower work function on the glass substrate 101. The ITO strip 102 having one higher work function is employed as an anode for injecting the hole and the anode strip 105 having one lower work function is employed as a cathode for injecting the electron.
FIG. 2A to FIG. 2F illustrates a perspective view showing an organic EL display panel in accordance with the related art. First, as illustrated in FIG. 2, a transparent ITO strip 102 is formed on the glass substrate 101 for applying the anode. In this case, an ITO strip 102-A having a short length is also formed between the bulkheads 107 for extracting the anode strip 105 with ease.
And then, as illustrated in FIG. 2B, the supplement electrode 103 is formed of such conductive metal as Mo and Cr. In this instance, if a width of the supplement electrode 103 is wider than the ITO strip 102 at a location where the sealant 108 and the supplement electrode 103 are crossed, the sealant 108 on the supplement electrode 103 is not hardened □□ when the sealant 108 is hardened by using UV. Therefore, the width of the supplement electrode 103 at the location where the sealant 108 and the supplement electrode 103 are crossed is set narrower than the ITO strip 102 thereunder.
Subsequently, as illustrated in FIG. 2C and FIG. 2D, the ITO strip 102 further includes the insulating film 106 for insulating the bulkhead 107 from the anode strip 105. In this case, the insulating film 106 is formed in a blended form of an organic matter, an inorganic matter, and a macromolecule.
As illustrated in FIG. 2E and FIG. 2F, an organic layer 104 is formed on top of the insulating film 106 and the bulkhead 107, and then the anode strip 105 including Mg—Ag compound metal and aluminum or other conductive matter is formed. Finally, the seal-cover 109 is adhered by using the sealant 108.
FIG. 3 illustrates a floor plan showing an organic EL display panel after the glass substrate and the seal-cover are adhered by using the sealant in accordance with the related art.
As illustrated in FIG. 3, when the glass substrate 101 and the seal-cover 109 are adhered by using the sealant 108, there is a problem that the sealant 108 is injected along the bulkhead 107 into an emitting cell. The problem is described referring to FIG. 4A and FIG. 4B.
FIG. 4A illustrates a cross-sectional view of the display panel illustrated in FIG. 3 in accordance with an A direction, and FIG. 4B illustrates a cross-sectional view of the panel illustrated in FIG. 3 in accordance with a B direction.
As illustrated in the drawings, when the sealant 108 is in contact with the bulkhead 107, the sealant 108 is injected along the bulkhead 107 into the emitting cell. Then, the sealant 108-A influences the anode strip and the organic matter, thereby resulting a problem of an inferior emitting cell.